03-31-2016, 07:56 PM
Do you have the problem of receiving one frequency at two or three spots on the dial in the SW band?
EDIT:
I also noticed that I can readjust the SW antenna trimmer at 5MHz and the signal level of WWV increases.
To me that seems like a tracking error in the RF stages, but it would have to be something that only affects the SW band.
Discovered there are two settings of the SW oscillator trimmer that will provide a peak at 10.8 MHz. One setting causes a major drop in signal around the middle of the band and the other setting does not. Think that explains my antenna trimmer issue. I had the SW oscillator trimmer set to the wrong peak which in this instance was the peak that produced more negative AVC voltage.
Also I put a 2700pF mica cap in series with the 3000pF cap and it brought WWV in at just under 5MHz on the dial. I am thinking maybe 100pF or so of capacitance in parallel with the 2700pF cap might just get it right.
EDIT:
I also noticed that I can readjust the SW antenna trimmer at 5MHz and the signal level of WWV increases.
To me that seems like a tracking error in the RF stages, but it would have to be something that only affects the SW band.
Discovered there are two settings of the SW oscillator trimmer that will provide a peak at 10.8 MHz. One setting causes a major drop in signal around the middle of the band and the other setting does not. Think that explains my antenna trimmer issue. I had the SW oscillator trimmer set to the wrong peak which in this instance was the peak that produced more negative AVC voltage.
Also I put a 2700pF mica cap in series with the 3000pF cap and it brought WWV in at just under 5MHz on the dial. I am thinking maybe 100pF or so of capacitance in parallel with the 2700pF cap might just get it right.
